IBU calculations on BeerSmith

[mrnice4884]

I was wondering if anyone had any problems with the IBU calculations on BeerSmith. I copied this recipe from online: http://hopville.com/recipe/285906/ameri ... opia-clone. I get a 18.1 IBU for the specific hops and malt quantities. I also triple checked the numbers. According to the recipe though it says it should be 32.5 IBU and that 18 is HBU. Not sure if anyone had any suggestions. It's not the first time IBUs have been much different to recipes I've copied from online. Thanks, Mr NICE

[warra48]

I've tried to input the recipe into my BS2, but I don't want to change my setup from metric to US. I note it's supposed to be a 20 gallon recipe, and all the weights are in pounds and ounces?

Can you post your BS recipe, and I'll check for you?

[mrnice4884]

at the bottom of the webpage from link above,if you click on metric units, it will convert the recipe to metric. Thanks for checking.

[warra48]

I'll check for you tomorrow. Bedtime for this old codger right now.

[warra48]

I've finally put it through BS2 after changing the recipe to metric.

Something doesn't compute!

I allowed 44 litres pre-boil at SG 1.168, to give a mash efficiency of 80%.

I input the hops at the stated AA%, and changed the type to Leaf. The recipe quotes Tinseth method, which is what I have my program set to.

I end up with 17.1 IBU, and a Bitterness Ratio of 0.088 (IBU/SG). That's about half of the quoted recipe.

It's a mystery to me, but I suspect they have underquoted the hop quantities. For example, I brewed an AIPA not long ago, and used 155 grm of hop pellets in a 23 litre brew, and that included Tomahawk which is 14% AA.
The quoted recipe used just 224 gr of leaf hops in a 38 litre brew, and none of the hops were higher than 4.7% AA.

If I were you, I'd just double the hop quantities. You can't necessarily take everything published on the internet as gospel!

[Flux]

I too am having trouble with this thing on BeerSmith...

For example I'm wanting to put down a 23 lt. extract coopers pale ale using Challenger as my hop addition to try and replicate there yeast, which I can't. Anyway when I enter the ingredients in BeerSmith "Australian Pale Ale Extract (Coopers)" with a value of Weight - 1.7kg, Colour - 90EBC, Bitterness - 340IBU. To try and work out how much Challenger to add to the boil. This is where the problem starts as it says 340IBU- gal/lb for the tin alone, so then you enter the ingredient and it has a bitterness through the roof of 187.4 IBU's on the style guide comparison before any hop additions?
What is the problem here, what am I doing wrong? I haven't had a value before for can bitterness and now trying to use it in BeerSmith I cannot figure out how to transpose it to work?

If I remove the IBU value of 340 in the can spec everything works but I know that the can will have an IBU value but surely not 340IBU's for 1.7kg's?

Any help as to what to do here is appreciated.
Thanks in advance.

[warra48]

Fortunately, this subject has been covered in some depth on this forum.

Have a read through this Topic, it's only 3 pages, so not too long.
I'm hopeful it will provide you with the information you need.

Once you've worked your way through that, come back if you still have further questions.

http://www.homebrewandbeer.com/forum/viewtopic.php?f=2&t=9932&hilit=kit+IBU

[emnpaul]

I too am having trouble with this thing on BeerSmith...

For example I'm wanting to put down a 23 lt. extract coopers pale ale using Challenger as my hop addition to try and replicate there yeast, which I can't. Anyway when I enter the ingredients in BeerSmith "Australian Pale Ale Extract (Coopers)" with a value of Weight - 1.7kg, Colour - 90EBC, Bitterness - 340IBU. To try and work out how much Challenger to add to the boil. This is where the problem starts as it says 340IBU- gal/lb for the tin alone, so then you enter the ingredient and it has a bitterness through the roof of 187.4 IBU's on the style guide comparison before any hop additions?
What is the problem here, what am I doing wrong? I haven't had a value before for can bitterness and now trying to use it in BeerSmith I cannot figure out how to transpose it to work?

If I remove the IBU value of 340 in the can spec everything works but I know that the can will have an IBU value but surely not 340IBU's for 1.7kg's?

Any help as to what to do here is appreciated.
Thanks in advance.

As the kit is sold in Kg's as opposed to litres it makes it a weight to volume dilution. You need to multiply the stated IBU by the weight of the tin (in KG) then divide by your final volume (in Litres).

So for a 23 litre brew: (340 X 1.7)/23 = 25 IBU

Can't tell you how to enter this into Beersmith as I am on Brewmate.

Hope this helps.

[Flux]

As the kit is sold in Kg's as opposed to litres it makes it a weight to volume dilution. You need to multiply the stated IBU by the weight of the tin (in KG) then divide by your final volume (in Litres).

So for a 23 litre brew: (340 X 1.7)/23 = 25 IBU

Can't tell you how to enter this into Beersmith as I am on Brewmate.

Hope this helps.

Thanks mate your a star that helps heaps! much appreciated.This is indeed the problem as BeerSmith doesn't calculate the IBU dilution with batch volume for some reason?
Will let BeerSmith know as it will no doubt stump a few people when they come across it